High potential lead-in



Sept 4, 1934- K. BAHRMANN ,972,78

HIGH POTENTIAL LEAD- IN Filed Dec. ll, 1930 W, bw?) Patented Sept. 4, 1934 UNITED STATES PATENT OFFICE HIGH POTENTIAL LEAD-IN Application December 11, 1930, Serial No. 501,657 In Germany December 13, 1929 l Claim.

This invention has reference to high potential coils in which the windings thereof are arranged in layers and has for its object to provide a coil winding by which potential control of a high potential lead-in insulator is positively effected,

that is, a denite potential is impressed on the insulating material. In carrying out the invention, the conductive intermediate layers of a high potential lead-in of the known condenser type are replaced by the separate layers of the layerwise windings forming the coil, these windings being so disposed and connected between the terminals of the lead-in that they effect control of the applied potential without the necessity of providing for that purpose a potential regulating transformer. With this arrangement one end of the coil or the terminal thereof is connected to the high potential line, the other being preferably grounded.

The coil forming the subject-matter of this invention will be more fully described in the following, reference being made therein to the annexed drawings showing one application of layerwise windings and in which the potential control is eiiected according to the ohmic resistance of the coil or its self-induction and independently of the conditions of the dielectric or of the series connected layers of insulating material interposed between the several winding layers. The

self-induction can be increased by means of an open or closed iron core tted in the coil spool resulting in considerable reduction in the number and size of the winding layers forming the coil. A coil of this nature can therefore be readily adapted for use in, for example, a voltage measuring transformer.

In the drawing:

Figure 1 shows an arrangement of a high potential coil associated with a closed iron core.

Figure 2 is a top plan View thereof, and

Figure 3 is a circuit diagram of the arrangement shown in Figure 1.

Referring to the drawing, there is shown a constructional arrangement of an insulated high potential coil comprising a rectangular square core 1 having a vertical arm 5. Upon this arm is mounted an insulating body 8 having embedded therein a high potential coil or winding 3 and a secondary winding 7. The other vertical arm 21 65 of the iron core supports an insulating body 22 similar to the body 8 and having embedded therein a plurality of separate unconnected layerwise windings 22a forming a condenser lead-in arrangement of known type. The high potential is applied to the free end of the outer winding layer of the winding 3 as indicated at 10, the layer being conductively connected to the outer layer of the condenser-like windings 22a. The inner layer or the coil 3 is at its free end connected to 75 the arm 5 of the core as at 9, said core being grounded and having wound thereon the secondary winding '7. This winding '7 may have connected thereacross a voltmeter V or alternatively may be coupled to a generator G as shown in broken lines. The connections of the windings are shown diagrammatically in Figure 3.

I claim:

A high potential lead-in device comprising in combination an insulating body, a coil of conductive material embedded within said body consisting of a plurality of superimposed, coaxial winding layers having input and output terminals and a closed iron core of which one limb carries the said insulating body, the other carrying a further insulating body having condenser-like windings.

KARL BAHRMANN. 

